The FDA extends its review date for the MS drug Tysabri - produced by Biogen Idec (BIIB) and...

The FDA extends its review date for the MS drug Tysabri - produced by Biogen Idec (BIIB) and Elan (ELN) - indicating it needs the extension to review changes in the risk evaluation and mitigation strategies for the drug. Premarket: BIIB -6%, ELN inactive.